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Polypropylene (PP) is a highly non-polar polymer. Where as the clay is a polar material. Hence generally we get poor dispersion out of it. In this work, effort has been taken to improve the dispersion of clay in to polypropylene matrix. Clay was modified with Poly (oxypropylene) ammonium chloride. Composites were prepared by melt blending method in a twin screw extruder. Three different ratios namely 1.5, 3.0, and 4.5 weight % loadings of clay were adopted to prepare these composites by this technique. Their structures were characterized by FTIR, x-ray diffraction (XRD). Notable change in the crystallization and melting temperatures were observed by differential scanning calorimetry (DSC). The distribution of clay in the matrix was also studied through optical microscope (OM) and scanning electron microscope (SEM). The effect of clay modification on the performance of the composites was studied.

Polymers have entropy nearly zero which cause mixing of different polymers or with the fillers become very difficult. There is generally a third component necessary which is called surfactant to enhance the miscibility. The surfactant reduces interfacial tension and improves the interfacial adhesion. In this work, tailored polymeric surfactant is designed and utilized for dispersing the clay in nano scale in to the polymer matrix Polypropylene (PP). These were prepared directly from Na+ Bentonite by reactive processing in which melt intercalation technique was carried. They are Polypropylene-g-acrylic amido Poly(oxypropylene) ammonium chloride (POPA). This ammonium salt was prepared from diamine and Polypropylene-g-acrylic acid by the formation of amido amine and sequentially neutralized it with the hydrochloric acid solution. The amido amine formation was verified by the FTIR technique. Clay loading was kept at 5 weight % by this new technique. Their structures were characterized by x-ray diffraction (XR...

Engineering nanostructures with complete control over the shape, composition, organization of the surface structures, and function remains a major challenge. In my work, I have fabricated nanostructures using functional polymer motifs and nanoparticles (NPs) via supramolecular and non-supramolecular interactions. In one of the approaches to generate nanostructures, I have integrated top-down approaches such as nanoimprint lithography, electron-beam lithography, and photolithography with the self-assembly (bottom-up) of NPs to provide nanostructures with tailored shape and function. In this strategy, I have developed a geometrically assisted orthogonal assembly of nanoparticles onto polymer features at precisely defined locations. This versatile NP functionalization method can be used to fabricate protein resistant patterned surfaces to provide essentially complete control over cellular alignment, making them promising biofunctional structures for cell patterning. In another approach, I have utilized self-assembly of dendrimers and NPs without preformed templates to generate nanostructures that can be used as chemoselective membranes for the separation of small and biomacromolecules.

ZnO-polypropylene nanocomposites (nano-PP) were prepared using nanoparticles of ZnO stabilized by soluble starch (nano-ZnO) as filler in PP by the melt mixing process. X-ray diffraction (XRD) and other spectroscopic analysis—ultraviolet–visible (UV–vis), Fourier transform infrared (FTIR) and photoluminescence—revealed the presence and characteristics of nano-ZnO in the composites. The presence of ZnO imparts whiteness, while starch increased the yellowing of polymers. The nanocomposites were analyzed for changes in optical, mechanical, electrical and rheological properties, as influenced by the increasing concentration of nano-ZnO. The mechanical properties were marginally increased and the dielectric strength of the nano-PP increased to a notable level. By monitoring the evolution of the carbonyl absorption bands from FTIR analysis, the efficacy of nano-ZnO in the reduction of photo-degradation due to UV irradiation was demonstrated. The excellent antibacterial activity exhibited by nano-ZnO impregnated PP against two human pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumoniae, makes it a suitable candidate for food packaging applications.